Suction powered pool cleaning robots are adapted for use for cleaning a pool while being powered by an external suction (or pump) and filter system. The robot is designed to traverse, e.g., the bottom and/or side surfaces of the pool when attached to a hose of the suction system. Water which is drawn through the hose is typically filtered and returned to the pool. Thus, a main function of the robot is to carry the hose about the pool surfaces to be cleaned. Such robot s may scan along a predetermined path or pre determined direction changes based on arrangement of mechanical elements.